The Government has announced plans to increase its reliance on nuclear power. Here, Peter Lloyd, the chairman of the Nuclear-free Local Authorities Committee, urges caution and points to existing West power stations which could be at long-term risk from flooding and coastal erosion. Last month the Prime Minister announced a review of policy in a move heralded as putting nuclear power back on the UK's energy agenda.

However, before Tony Blair gets too carried away with plans to build new nuclear power stations, he might like to stop and think carefully about where any new reactors could be located.

Nearly all of the country's existing nuclear power stations have been built on the coast so they can use the sea to obtain cooling water and dispose of waste. However, a recent study (see 1, below) by Nirex, the UK's nuclear waste agency, has shown many of these sites are vulnerable to coastal erosion and rising sea levels resulting from climate change.

The Nirex report reveals that at least 11 of Britain's nuclear sites are so low-lying that they could be drowned or damaged by rising seas. Nuclear power stations at Berkeley in Gloucestershire and Bradwell in Essex are virtually at sea level, and the report highlights the Dungeness nuclear plant in Kent, which is only two to five metres above sea level, as facing a "very high" risk from beach erosion .

The Sellafield nuclear complex in Cumbria and the nearby radioactive waste dump at Drigg are also highly vulnerable to coastal erosion, and other sites, including Sizewell, Hunterston, Wylfa, and Somerset's Hinkley Point, appear to be at long-term risk.

Nirex warns that "coastal erosion can be dramatic and may, for many, if not most sites, provide a far greater worry than sea level rise alone", and coastal erosion appears to pose the greatest threat to the two nuclear power plants at Hinkley Point.

Although the Hinkley Point site is protected by sea defences and rock outcrops on the coast in front of the power stations, the Nirex report points out that the cliff line and shoreline show evidence of active erosion by the very strong tides of the Bristol Channel and the wind and wave action to which the point is exposed.

Nirex believes that maintenance of the sea defences should ensure the integrity of the power station over the next 15 years, but over the next 100 years rising sea levels and strong tidal flows will isolate the headland on which it is situated.

Over the next 300 years, if coastal processes operate as predicted, the area may well be flooded and the site would be surrounded by sea on three sides.

Hinkley Point is likely to be a prime candidate for construction of a new reactor, should the Government say yes to a new generation of power stations following the recently announced energy review. Planning permission for construction of a pressurised water reactor at Hinkley was granted in 1990 following a two-year public inquiry.

Evidence presented at the inquiry threw the economic viability of the new reactor into question, and plans for its construction were quietly abandoned following privatisation of the electricity industry, but there is little doubt that the nuclear industry would be looking at the Hinkley Point plans again with renewed interest if the energy review favours the nuclear option.

However, it would be foolish to think that new reactors could be built at current sites without fully evaluating the risks of doing this. Environmental regulators are unlikely to consider man-made sea defences sufficient to protect new nuclear sites from rising sea levels and coastal erosion.

The Environment Agency recently announced that "we cannot accept that coastal defences can be designed to perform their intended function, without continual maintenance, over the long timescales (500 to thousands of years) required for them to have a mitigating effect on post-closure risks. These timescales are significantly longer than the period of active control assumed by BNFL".

(See note 2, below) If existing coastal reactor sites are ruled out, new nuclear power stations would have to be built inland on new, greenfield sites. This means that almost any undeveloped inland location that is accessible and a reasonable height above sea level could become a possible location for a new reactor.

Given current concerns about the construction of wind farms in some quarters, it seems certain that plans to build a nuclear power station at a greenfield site would provoke massive opposition.

In terms of cost, reliability, national security implications and potential to cut carbon emissions, clean renewable power sources and measures which reduce consumption and improve energy efficiency have the upper hand on nuclear power in any objective assessment of future energy supply.

This is why, just two years ago, the Government rejected nuclear power as an unattractive option for meeting Britain's electricity needs. Rather than being a saviour for the nuclear industry, climate change looks likely to become another nail in its coffin.

Instead of embarking on a new nuclear programme with all the risks it entails, we should be heavily investing in renewable energy and energy conservation to meet our future power needs.